diff --git a/src/lib/openjp2/opj_intmath.h b/src/lib/openjp2/opj_intmath.h
index 94512afc..73d08a28 100644
--- a/src/lib/openjp2/opj_intmath.h
+++ b/src/lib/openjp2/opj_intmath.h
@@ -102,6 +102,7 @@ Divide an integer and round upwards
 @return Returns a divided by b
 */
 static INLINE OPJ_INT32 opj_int_ceildiv(OPJ_INT32 a, OPJ_INT32 b) {
+  assert(b);
 	return (a + b - 1) / b;
 }